泡沫铝表面Ni-W共沉积及性能研究

Ni-W Co-deposition and Property of Closed Cell Aluminum Foam

目的进一步提高泡沫铝材料的强度及耐蚀特性,同时明确金属涂覆泡沫铝材料的综合耗能指标。方法对泡沫铝表面预镀镍层后,在硫酸盐体系下,利用脉冲电镀进行镍钨合金共沉积。通过准静态压缩测试及扫描电镜分析,得到泡沫铝、预镀镍泡沫铝及镍钨共沉积泡沫铝材料的特征曲线及变形模式,综合分析材料的增强机理及综合耗能指标。采用电化学测试对比分析材料耐蚀特性。结果泡沫铝表面共沉积镍钨合金层后,其峰值应力比镀镍泡沫铝平均提高了10%,较基体泡沫铝平均提高了约45%。强度提高来源于变形过程中包覆金属的支撑及铝基体-镍镀层界面处的拉伸撕裂。镍钨合金共沉积使泡沫铝的能量吸收增加38%,吸能效率有所提升,且其自腐蚀电位较镀镍泡沫铝及基体泡沫铝明显正移,腐蚀倾向及腐蚀速率降低。结论泡沫铝表面镍钨合金共沉积使其强度、耐蚀性较镀镍泡沫铝进一步提高。由于特征曲线及变形模式的改变,镍钨共沉积泡沫铝的耗能特性提升明显。

The work aims to improve the strength and corrosion resistance of aluminum foam and clarify the comprehensive energy consumption indicators of aluminum foam with metal coating.Closed aluminum foam was treated by pulse nickel-tungsten co-deposition process in sulfate system after nickel plating.The quasi-static compression and SEM were utilized to obtain the characteristic curve and deformation mode of aluminum foam,Ni coated aluminum foam and aluminum foam with Ni-W coating.Furthermore,the enhancement mechanism and energy consumption indicators of materials were analyzed comprehensively.Corrosion resistance of materials was investigated comparatively via electrochemical test.After nickel-tungsten co-deposition process,the peak stress of aluminum foam was 10%higher than that of aluminum foam with Ni coating and about 45%higher than the substrate aluminum foam.This was due to the support of the coating as well as the tearing effect between Al-Ni interface in the deformation process.The energy absorption of aluminum foam increased by 38%after nickel-tungsten co-deposition and the energy absorption efficiency of aluminum foam also increased.Meanwhile,the self-corrosion potential was obviously positively shifted compared with nickel-plated aluminum foam and substrate aluminum foam,and the corrosion tendency and corrosion rate reduced.Co-deposition of nickel-tungsten alloy on the surface of aluminum foam further improves its strength and corrosion resistance compared with nickel-plated foamed aluminum.Due to the change of the characteristic curve and deformation mode,the energy consumption characteristics of Ni-W co-deposition aluminum foam are improved significantly.